Recently, transcranial electrical stimulation (tES) has gained increasing popularity among researchers, especially for recovery and improvement, but interpretation of these results is difficult due to variations in study methods and outcome measurements. The main goal of this study was to better understand the postural and balance indicators affected by cerebellar tES, as the cerebellum is the main brain region responsible for controlling balance. For this systematic literature review, three databases were searched for articles where the cerebellum was stimulated by any type of tES in either healthy participants or those with neurologic disorders. Postural, dynamic, and/or static stability measurements were recorded, and risk of bias was assessed on the PEDro scale. A total of 21 studies were included in the analysis. 17 studies reported improvements after application of tES. 14 studies stimulated the cerebellum unilaterally and 15 used this modality for 20 min. Moreover, all studies exclusively used transcranial direct current as the type of stimulation. Evaluation of PEDro results showed that studies included in the analysis utilized good methodology. Although there were some inconsistencies in study results, overall, it was demonstrated that tES can improve balance and postural index under both healthy and neurological conditions. Further research of bilateral cerebellar stimulation or the use of transcranial alternating current stimulation, transcranial random noise stimulation, and transcranial pulsed current stimulation is needed for a more comprehensive assessment of the potential positive effects of cerebellar tES on the balance system.
Hypofunctioning of NMDA receptors, and the resulting shift in the balance between excitation and inhibition, is considered a key process in the pathophysiology of schizophrenia. One important manifestation of this phenomenon is changes in neural oscillations, those above 30 Hz (i.e., gamma-band oscillations), in particular. Although both preclinical and clinical studies observed increased gamma activity following acute administration of NMDA receptor antagonists, the relevance of this phenomenon has been recently questioned given the reduced gamma oscillations typically observed during sensory and cognitive tasks in schizophrenia. However, there is emerging, yet contradictory, evidence for increased spontaneous gamma-band activity (i.e., at rest or under baseline conditions). Here, we use the sub-chronic phencyclidine (PCP) rat model for schizophrenia, which has been argued to model the pathophysiology of schizophrenia more closely than acute NMDA antagonism, to investigate gamma oscillations (30-100 Hz) in the medial prefrontal cortex of anesthetized animals. While baseline gamma oscillations were not affected, oscillations induced by train stimulation of the posterior dorsal CA1 (pdCA1) field of the hippocampus were enhanced in PCP-treated animals (5 mg/kg, twice daily for 7 days, followed by a 7-day washout period). This effect was reversed by pharmacological enhancement of endocannabinoid levels via systemic administration of URB597 (0.3 mg/kg), an inhibitor of the catabolic enzyme of the endocannabinoid anandamide. Intriguingly, the pharmacological blockade of CB1 receptors by AM251 unmasked a reduced gamma oscillatory activity in PCP-treated animals. The findings are consistent with the observed effects of URB597 and AM251 on behavioral deficits reminiscent of the symptoms of schizophrenia and further validate the potential for cannabinoid-based drugs as a treatment for schizophrenia.
- MeSH
- amidohydrolasy * antagonisté a inhibitory metabolismus MeSH
- antagonisté excitačních aminokyselin farmakologie aplikace a dávkování MeSH
- benzamidy * farmakologie MeSH
- endokanabinoidy metabolismus MeSH
- fencyklidin * farmakologie MeSH
- gama rytmus EEG fyziologie účinky léků MeSH
- karbamáty * farmakologie MeSH
- krysa rodu rattus MeSH
- kyseliny arachidonové metabolismus farmakologie MeSH
- modely nemocí na zvířatech MeSH
- piperidiny * farmakologie MeSH
- polynenasycené alkamidy metabolismus farmakologie MeSH
- potkani Sprague-Dawley MeSH
- prefrontální mozková kůra účinky léků metabolismus patofyziologie MeSH
- pyrazoly farmakologie MeSH
- schizofrenie * patofyziologie metabolismus farmakoterapie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Botulinum toxin type A (BoNT) is considered an effective therapeutic option in cervical dystonia (CD). The pathophysiology of CD and other focal dystonias has not yet been fully explained. Results from neurophysiological and imaging studies suggest a significant involvement of the basal ganglia and thalamus, and functional abnormalities in premotor and primary sensorimotor cortical areas are considered a crucial factor in the development of focal dystonias. Twelve BoNT-naïve patients with CD were examined with functional MRI during a skilled hand motor task; the examination was repeated 4 weeks after the first BoNT injection to the dystonic neck muscles. Twelve age- and gender-matched healthy controls were examined using the same functional MRI paradigm without BoNT injection. In BoNT-naïve patients with CD, BoNT treatment was associated with a significant increase of activation in finger movement-induced fMRI activation of several brain areas, especially in the bilateral primary and secondary somatosensory cortex, bilateral superior and inferior parietal lobule, bilateral SMA and premotor cortex, predominantly contralateral primary motor cortex, bilateral anterior cingulate cortex, ipsilateral thalamus, insula, putamen, and in the central part of cerebellum, close to the vermis. The results of the study support observations that the BoNT effect may have a correlate in the central nervous system level, and this effect may not be limited to cortical and subcortical representations of the treated muscles. The results show that abnormalities in sensorimotor activation extend beyond circuits controlling the affected body parts in CD even the first BoNT injection is associated with changes in sensorimotor activation. The differences in activation between patients with CD after treatment and healthy controls at baseline were no longer present.
- MeSH
- aferentní nervové dráhy diagnostické zobrazování účinky léků MeSH
- botulotoxiny typu A terapeutické užití MeSH
- dospělí MeSH
- kyslík krev MeSH
- lidé středního věku MeSH
- lidé MeSH
- magnetická rezonanční tomografie metody MeSH
- neparametrická statistika MeSH
- nervosvalové látky terapeutické užití MeSH
- počítačové zpracování obrazu MeSH
- psychomotorický výkon účinky léků MeSH
- senioři MeSH
- senzorimotorický kortex diagnostické zobrazování účinky léků MeSH
- tortikolis * diagnostické zobrazování farmakoterapie patofyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
We report on the effects of prenatal alcohol exposure on resting-state brain activity as measured by magnetoencephalography (MEG). We studied 37 subjects diagnosed with fetal alcohol spectrum disorder in one of three categories: fetal alcohol syndrome, partial fetal alcohol syndrome, and alcohol-related neurodevelopmental disorder. For each subject, the MEG signal was recorded for 60 s during rest while subjects lay supine. Using time series analysis, we calculated the synchronous neural interactions for all pair-wise combinations of 248 MEG sensors resulting in 30,628 partial correlations for each subject. We found significant differences from control subjects in 6.19 % of the partial zero-lag crosscorrelations (synchronous neural interactions; Georgopoulos et al. in J Neural Eng 4:349-355, 2007), with these differences localized in the right posterior frontal, right parietal, and left parietal/posterior frontal regions. These results show that MEG can detect functional brain differences in the individuals affected by prenatal exposure to alcohol. Furthermore, these differences may serve as a biomarker for future studies linking symptoms and signs to specific brain areas. This may lead to new insights into the neuropathology of fetal alcohol spectrum disorders.
- MeSH
- alkoholy škodlivé účinky MeSH
- analýza rozptylu MeSH
- časové faktory MeSH
- dítě MeSH
- dospělí MeSH
- lidé MeSH
- magnetoencefalografie MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mozková kůra patofyziologie MeSH
- neurovývojové poruchy etiologie MeSH
- spektrum vrozených alkoholových poruch etiologie MeSH
- studie případů a kontrol MeSH
- těhotenství MeSH
- zpožděný efekt prenatální expozice patologie MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
We studied whether one session of high-frequency repetitive transcranial magnetic stimulation (rTMS) applied over either the right or left dorsolateral prefrontal cortex would induce any measurable changes in the Tower of London spatial planning task performance in patients with Parkinson's disease (PD). Ten patients with PD (with no dementia and/or depression) entered the randomized, sham-stimulation-controlled study with a crossover design. Active and placebo rTMS were applied over either the left or the right dorsolateral prefrontal cortex (in four separate sessions) in each patient. The order of sessions was randomized. The Tower of London task was performed prior to and immediately after each appropriate session. The "total problem-solving time" was our outcome measure. Only active rTMS of the right dorsolateral prefrontal cortex induced significant enhancement of the total problem-solving time, p = 0.038. Stimulation of the left prefrontal cortex or sham stimulations induced no significant effects. Only rTMS applied over the right dorsolateral prefrontal cortex induced positive changes in the spatial planning task performance in PD, which further supports the results of functional imaging studies indicating the causal engagement of the right-sided hemispheric structures in solving the task in this patient population.
- MeSH
- exekutivní funkce fyziologie MeSH
- funkční lateralita fyziologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mapování mozku * MeSH
- neuropsychologické testy MeSH
- Parkinsonova nemoc patologie MeSH
- prefrontální mozková kůra patofyziologie MeSH
- řešení problému MeSH
- senioři MeSH
- transkraniální magnetická stimulace * MeSH
- záznam o duševním stavu MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- randomizované kontrolované studie MeSH
We studied whether the cognitive event-related potentials (ERP) in the subthalamic nucleus (STN) are modified by the modulation of the inferior frontal cortex (IFC) and the dorsolateral prefrontal cortex (DLPFC) with repetitive transcranial magnetic stimulation (rTMS). Eighteen patients with Parkinson's disease who had been implanted with a deep brain stimulation (DBS) electrode were included in the study. The ERPs were recorded from the DBS electrode before and after the rTMS (1 Hz, 600 pulses) over either the right IFC (10 patients) or the right DLPFC (8 patients). The ERPs were generated by auditory stimuli. rTMS over the right IFC led to a shortening of ERP latencies from 277 +/- 14 ms (SD) to 252 +/- 19 ms in the standard protocol and from 296 +/- 17 ms to 270 +/- 20 ms in the protocol modified by a higher load of executive functions (both P < 0.01). The application of rTMS over the DLPFC and the sham stimulation over the IFC showed no significant changes. The shortening of ERP latency after rTMS over the right IFC reflected the increase in the speed of the cognitive process. The rTMS modulation of activity of the DLPFC did not influence the ERP. Connections (the IFC-STN hyperdirect pathway) with the cortex that bypass the BG-thalamocortical circuitries could explain the position of the STN in the processing of executive functions.
- MeSH
- akustická stimulace MeSH
- analýza rozptylu MeSH
- čelní lalok patofyziologie MeSH
- elektroencefalografie MeSH
- evokované potenciály fyziologie MeSH
- exekutivní funkce fyziologie MeSH
- implantované elektrody MeSH
- lidé středního věku MeSH
- lidé MeSH
- mapování mozku MeSH
- nervové dráhy patofyziologie MeSH
- nucleus subthalamicus patofyziologie MeSH
- Parkinsonova nemoc patofyziologie MeSH
- počítačové zpracování signálu MeSH
- psychomotorický výkon fyziologie MeSH
- reakční čas MeSH
- sluchová percepce fyziologie MeSH
- transkraniální magnetická stimulace metody MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Motor cortex stimulation (MCS) has gained a significant role in treatment of neuropathic pain. In order to evaluate effect of MCS in experimental animals we applied MCS to rats with neuropathic pain, which was evoked by chronic constriction injury (CCI) to the left sciatic nerve. Pain thresholds of both hind limbs were measured before, immediately after MCS, 1 h after MCS and 1 day after MCS. Effect of the stimulation was studied with respect to laterality (contralateral and ipsilateral MCS) and duration (short-term 10-min and long-term 1-h stimulation). It was found out that in control rats MCS did not affect thermal nociceptive thresholds. However, in CCI animals following results were obtained: difference score (difference in paw withdrawal latency between ligated and non-ligated hind limb) significantly decreased after both short- and long-term contralateral MCS; the difference score after the long-term ipsilateral MCS (related to the ligated hind limb) was not significantly different from that of intact animals; the effects of the contralateral short-term and the ipsilateral long-term stimulation faded within 1 h after the end of MCS, while the effect of the contralateral long-term MCS remained 1 h after the end of the MCS and faded within 24 h. It is concluded that MCS in experimental animals exerts similar effects as in human suffering from neuropathic pain and that the effect might be evoked from both cerebral cortices.
- MeSH
- bolest patofyziologie prevence a kontrola MeSH
- elektrostimulační terapie metody MeSH
- krysa rodu rattus MeSH
- měření bolesti metody MeSH
- motorické korové centrum fyziologie MeSH
- nemoci sedacího nervu patofyziologie MeSH
- potkani Wistar MeSH
- stenóza patofyziologie prevence a kontrola MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- srovnávací studie MeSH
Several functional MR imaging studies evaluating the lateralisation of linguistic functions in patients who underwent Wada testing have been reported. There is extensive variance in the Laterality index (LI) calculation across the studies, and the optimal calculation method remains unclear. We attempted to calculate the LI in different ways in the same subjects, in order to find the LI calculation method with the highest correlation to the Wada test. Fifteen patients (10 females, 5 males) suffering from medically intractable temporal lobe epilepsy (TLE) (12 left, 3 right) were admitted for the study. The patients underwent a standardized bilateral intracarotid short-acting barbiturate test. Language testing included spontaneous speech, oral comprehension, reading, object and picture naming, and repetition. All the tasks were scored separately in order to increase the possibility of correlation between Wada and LI. A silent phonemic verbal fluency task (VFT) was used as a language paradigm for functional measurement. Regions of interest (ROIs), with a known association with language function (Broca's area, the lateral prefrontal cortex, etc.), were defined. First, the LIs were calculated from the ROIs using a previously reported method (simple suprathreshold count). Next, we used several new methods of LI calculation (t-weighting of voxels, methods independent of the choice of the statistical threshold, etc.) The most significant correlation with Wada was proven in the LIs that were evaluated from Broca's area (up to R = 0.94, P = 1 x 10(-7)). However, the new LI calculation methods used in the present study did not produce a statistically significant benefit in comparison to previously reported methods.
- MeSH
- amobarbital diagnostické užití MeSH
- čelní lalok anatomie a histologie fyziologie MeSH
- čtení MeSH
- dospělí MeSH
- epilepsie temporálního laloku diagnóza patofyziologie MeSH
- financování organizované MeSH
- funkční lateralita fyziologie MeSH
- hypnotika a sedativa diagnostické užití MeSH
- jazyk (prostředek komunikace) MeSH
- jazykové testy MeSH
- lidé MeSH
- magnetická rezonanční tomografie metody MeSH
- mapování mozku metody MeSH
- mozková kůra anatomie a histologie fyziologie MeSH
- nervová síť anatomie a histologie fyziologie MeSH
- neuropsychologické testy MeSH
- percepce řeči fyziologie MeSH
- prediktivní hodnota testů MeSH
- řeč fyziologie MeSH
- verbální chování fyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
Individual nuclei of the auditory pathway contribute in a specific way to the processing of complex acoustical signals. We investigated the responses of single neurons to typical guinea pig vocalizations (purr, chutter, chirp and whistle) in the ventral part of the medial geniculate body (MGB) of anesthetized guinea pigs. The neuronal and population peristimulus time histograms (PSTHs) reflected the repetition frequency of individual phrases in the calls. The patterns of PSTHs correlated well with the sound temporal envelope in calls with short phrases (purr, chirp). The dominant onset character of the neuronal responses resulted in a lower correlation between the sound envelope and the PSTH pattern in the case of longer calls (chutter and whistle). A time-reversed version of whistle elicited on average a 13% weaker response than did the natural whistle. The rate-characteristic frequency (CF) profile provided only a coarse representation of the sound frequency spectrum without detailed information about the individual spectral peaks and their relative magnitudes. In comparison with the inferior colliculus (Suta et al. in J Neurophysiol 90:3794-3808, 2003), the processing of species-specific vocalizations in the MGB differs in: (1) a less precise representation of the temporal envelope in the case of longer calls, but not in the case of calls consisting of one or more short phrases; (2) a less precise rate-CF representation of the spectral envelope in the case of low-frequency calls, but not in the case of broad-band calls; (3) a smaller difference between the responses to natural and time-reversed whistle.
- MeSH
- akční potenciály fyziologie MeSH
- akustická stimulace MeSH
- časové faktory MeSH
- druhová specificita MeSH
- financování organizované MeSH
- metathalamus cytologie fyziologie MeSH
- morčata MeSH
- neurony fyziologie MeSH
- reakční čas fyziologie MeSH
- sluchová percepce fyziologie MeSH
- spektrální analýza MeSH
- vokalizace zvířat fyziologie MeSH
- vztah dávky záření a odpovědi MeSH
- zvířata MeSH
- Check Tag
- morčata MeSH
- ženské pohlaví MeSH
- zvířata MeSH
The treatment of radicular pain is mainly empirical because there are only few experimental studies dealing with morphological changes during compression radiculopathy. The goal of the study was to investigate changes in the morphology of myelinated axons during spinal root compression and the influence of decompression in a new rat model. The number of myelinated axons and their diameter were measured at 1, 2, 5, and 8 weeks during compression of the dorsal spinal root. The same approach was applied for 1-week compression followed by decompression for 1 or 2 weeks and compression for 5 weeks followed by 3-week decompression. A decrease in the number of myelinated axons (particularly those of large diameters) occurred after compression for 1 week. Continued compression for up to 8 weeks resulted in centripetal increase in the number of myelinated axons and the persistence of a small fraction of large myelinated axons at the site of compression. After that time, a decreased number of axons and a reduced fraction of large myelinated axons occurred again. Decompression after 1-week compression caused a rapid increase in the number of both small and large myelinated axons within the spinal root including the site of compression. A small fraction of regenerated axons was found after 5-week compression followed by 3-week decompression. Finally, we investigated the time course of the temporary increase in the number of regenerated myelinated axons during dorsal root compression for up to 8 weeks. The efficacy of decompression was superior when applied one week after compression or after regress of the acute phase of aseptic inflammation associated with fragility of spinal root. The results of the study verify the need for early surgical decompression to prevent irreversible damage of the spinal roots.
- MeSH
- časové faktory MeSH
- chirurgická dekomprese MeSH
- financování organizované MeSH
- krysa rodu rattus MeSH
- lumbalgie etiologie patofyziologie patologie MeSH
- míšní kořeny patofyziologie patologie zranění MeSH
- modely nemocí na zvířatech MeSH
- nervová vlákna myelinizovaná patologie MeSH
- počet buněk MeSH
- potkani Wistar MeSH
- radikulopatie patofyziologie patologie MeSH
- regenerace nervu fyziologie MeSH
- úžinové syndromy chirurgie patofyziologie patologie MeSH
- Wallerova degenerace etiologie patofyziologie patologie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- ženské pohlaví MeSH
- zvířata MeSH